Increasing demand for subsea wireless communications

WFS reports that the use of its subsea wireless communications and control systems is being increased for applications such as asset integrity management, video and data transmission.

WFS reports that the use of its subsea wireless communications and control systems is being increased for applications such as asset integrity management, video and data transmission.

WFS Technologies was founded in 2003 by Brendan Hyland. Much of WFS's early work in underwater radio was for defence applications, where RF (radio frequency) had been used extensively in the past for submarine communications.

Over 5 years ago, WFS identified a market in the subsea oil and gas industry for shortrange high-speed wireless communications, similar to the functionality delivered by Bluetooth and wi-fi in homes, offices and industrial facilities.

WFS' initial focus of doing business was in the Gulf of Mexico but its wireless subsea technology has gradually penetrated North Sea, South East Asia, Australia and West Africa. In the last 5 years the company has delivered more than 7,000 communication and control devices around the world.

'North Sea operators are using our wireless instrumentation to monitor the integrity of subsea equipment', said Ian Crowther, executive vice president of WFS, speaking at the Digital Energy Journal forum in Aberdeen on June 2 2014, 'Digital subsea - integrity management and monitoring.'

A new product recently added to the Seatooth family is Seatooth PPC, a wireless datalogger for pipeline pre-commissioning. Hydrotest data can be captured, stored and downloaded reliably at data rates of up to 156kbps.

Once the data is downloaded it can then be retrieved to the surface for analysis. This gives the operator permanent pre-commissioning data, indicating data about the pipeline and water temperature.

As an extension to the PPC product, WFS developed “Seatooth WiPS,” an integrated subsea system that provides real-time pressure data. It comprises a high accuracy pressure sensor, a wireless datalogger and an LED display and provides pressure measurements up to 20,000 psi in depths up to 4000m. This is used for hydrotest applications measuring pipeline pressure, or survey operations providing precise depth measurements.

Radio signals are unaffected by acoustic noise or biofouling, and are free from multipathing problems. The signals can be sent in the presence of gas bubbles or high turbidity.

“It is critical that power consumption during datalogging is low in order to maximise the deployment duration and capture as much monitoring data as possible”, Mr Crowther says.

“A number of factors help support long term deployments of wireless instrumentation systems,” he said.

“Firstly, Seatooth is a very low power technology: not much power is consumed when the system is in operation; also, it has an ultra-low power sleep mode which is quite unique.”

“Secondly, by transferring data at very high data rates the system is only in its operational mode for short periods of time, so it can stay in the sleep mode for longer consuming less power.”

“Thirdly, Seatooth systems operate as wireless controllers, devices can be switched on/off, or reconfigured over a wireless link, and this technique can be used to extend battery life.

“Finally, the batteries are electrically disconnected, but can be turned on wirelessly, and this allows the battery life to be further extended.

All of these factors, along with developments in battery technology, mean that we can deploy systems for periods of up to 10 years”.

“A common way of downloading subsea data is with the use of cables and connectors which are common sources of downtime, either through failure or servicing.

By transferring data wirelessly, the risk associated by aligning pins and servicing electrical connections is removed. Wireless collection of data is faster and more reliable than physically retrieving dataloggers”. Mr Crowther said.

Baker Hughes - Pipeline MonitoringIn a project with Baker Hughes, WFS supplied a Seatooth PPC system for wireless datalogging during pipeline pre-commissioning on a project in the Liwan 3-1 gas field South China Sea at water depth of 1000m.

The transmitter included a Seatooth PPC connected to a hydrotest skid and the receiver comprised a Seatooth PPC mounted on the remotely operated vehicle (ROV).

Previously, Baker Hughes was gathering this data with a ROV permanently stationed next to the pipelines taking readings from the sensors using a video camera and someone would write down in a book the these readings from a vessel above the pipeline. With the use of the Seatooth PPC data was downloaded wirelessly freeing manpower time and the ROV can be used to undertake other tasks.

i-Tech 7 - Wireless Video Monitoring

WFS Technologies wireless technology is being also used for inspection, monitoring and maintenance projects. In a project with i- Tech 7, WFS Technologies provided Seatooth Video, a subsea wireless video camera solution used for subsea construction and IRM activities as it provides a 2nd perspective on complex tasks and in difficult to access places.

Seatooth Video, mounted on a Centurion QX work class ROV was used by i-Tech 7 for Woodside in Australia during a maintenance project on the field of the North Rankin. The project was carried out on the NRA second Trunkline (2TL) which transports two phase gas condensate from offshore facilities on theNorth West Shelf to the Karratha Gas Plant.

The project team was seeking a small camera solution to mount on an intervention tool. The camera would help with the removal of an internal plug and make the inside of the tool visible during this operation.

The engineers at i-Tech 7 and Woodside recognised that cabling would be a hazard in the conditions where the job was located, and that by using Seatooth Video would remove the need for a cable between the ROV and camera.

The i-Tech 7 team needed to ensure that progress was being made as planned, to minimise risk, time and cost. Without visibility, there would be no way of knowing if the tool had connected with the plug inside the guide and successfully removed it.

Seatooth Video streamed live video from inside the tool while it was operational, providing images to support lining up of the tool with the plug. The job was completed safely and without incident, and in a shorter time frame than anticipated.

At the Digital Energy Journal conference, Mr Crowther presented a video from the i-Tech 7 project, showing the tool trying to align to the subsea plug. The video shows that during the first attempt the tool hadn’t grasped the plug properly. Without visibility from Seatooth Video, engineers would have risked damaging the plug which would have led into a major intervention task.

“WFS has also provided Seatooth Video deepwater systems to Fugro for the Moho Nord project in Congo. After this successful collaboration the companies agreed to enter a partnership to offer subsea wireless capability on all Fugro’s FCV Work Class ROVs”, Mr Crowther said.

Seatooth Video is available in three versions: Fixed Perspective with integrated lights, Pan- Tilt-Zoom enabling wide area coverage and the ability to zoom in on detail, and the third option of plugging in a third-party subsea camera.

You can watch a video of Mr Crowther’s talk and download slides at http://www.digitalenergyjournal.com/video/1333.aspx